Saturday, September 29, 2007

Spallating ideas like a heavy nucleus, and spelunking with permissive abandon through the subterranean network of conceptual pot-holes, here are today's ideas:

Klein bags: It is often the case that, once full, a small or medium-sized rubbish bag requires disposal itself, either in a larger bag, or a larger container. This is wasteful, and fails to exploit non-orientable topological surfaces, such as the Klein bottle topology, in which the inside is also the outside. Small bin liners should be given a Klein-bag topology, enabling the user to dispose of the bag inside itself.

Motorway electromagnets: Accidents on motorways cause interminable delays to those behind, due to the length of time it takes tow-trucks to reach the scene and clear the wreckage. Hence, large superconducting electromagnets, rather like those at CERN, should be installed along the hard shoulder of all motorways. When an accident occurs, CCTV should identify the location, and the magnets should be switched on at that point, instantly sucking the crashed cars off the motorway, and onto the hard shoulder, allowing traffic flow to resume.

Robot wars on Mars: In 2009, NASA will deploy a rover on Mars equipped with a laser. Ostensibly, the purpose of the laser is to vapourise rocks, prior to spectroscopic sampling. However, with some small modifications, this could become an offensive weapon, and should be employed whenever the Russians deploy a rover of their own, and attempt to plant a flag on the Martian surface.

Monday, September 24, 2007

This is the Z-machine at Sandia National Laboratories. (Click on the image to see it in its full glory). During the fraction of a second in which it operates, it discharges 80 times the entire world's electrical power output. Designed to study nuclear fusion using a so-called Z-pinch technique, the Z-machine releases an electromagnetic pulse, which creates this coruscating pattern of electrical discharges in the exterior laboratory.

The Manic Street Preachers have promised much over the years, without ever really delivering anything apart from a few good riffs, and some paranoid Marxist lyrics. 'Everlasting', however, is a beautiful song, and takes me back to October 1998, huddling in the sub-zero temperatures of a minimalistic Poole house-share, watching the Manics on 'Later, with Jools Holland'. Tempus fugit.

Tuesday, September 18, 2007

Before Bryan Appleyard's stint on the Sunday Times, he appeared in numerous small acting roles, with perhaps his most iconic performance being that of the 'Priest who kicks ass' in Peter Jackson's 1992 gorefest, Braindead. WARNING: contains gory comic violence.

Here's an interesting chap. Described by New Humanist magazine as an "astonishing one-man book factory," Joseph McCabe (1867–1955) wrote "prolifically on science, religion, politics, history and culture, writing nearly 250 books during his life." Most intriguingly, Joseph was once a Catholic priest, but sadly, in his case, there was to be no Technicolour Dreamcoat:

When his Christian faith deserted him towards the end of the nineteenth century he turned himself into what you might call a pious atheist, a zealous crusader in a holy war against religion. For the next six decades he would denounce the Catholic Church with a vehemence that often sounded more like Protestant fanaticism than cool rational atheism. He had managed to rid himself of the Christian attitude of humble reverence while retaining a fixed attitude of righteous indignation, and he never surrendered to the embraces of humour, let alone wit.

McCabe claimed that he was interested not in 'personal valuations or hopes' but only in plain 'historical facts'. He believed he had discovered a 'historical law' – let’s call it McCabe’s Law – which states that 'atheism grows in proportion to the growth of knowledge and freedom.' At the beginning of the twentieth century, he reckoned, atheism was expanding 'a hundred times more rapidly than any religion ever grew', and only a fool could doubt that the coming decades would witness 'a development of atheism immeasurably greater than has ever been known before'. His faith in the progress of reason would then provide the scaffolding for his Biographical Dictionary of Freethinkers (1920) and his Rationalist Encyclopedia (1948), works that provide a kind of roll-call of the saints of rationalism, ranked by their degree of conformity to McCabe’s law.

Andrew Liddle makes the interesting suggestion that inflation and dark matter could have a common source. If the hypothetical 'inflaton' field responsible for inflation actually existed, then, as a quantum field, it would have possessed inflaton particles as excitation quanta of the field. The conventional hypothesis is that, whilst dark matter particles interact gravitationally with the known particles of the Standard Model, they interact very rarely via the non-gravitational forces. As a particular consequence, dark matter neither absorbs nor scatters light from other sources, and, with the possible exception of annihilation processes, dark matter doesn't emit light. Liddle suggests that dark matter consists of inflaton particles left over from the inflationary era of the universe. For Liddle's idea to work, however, it is necessary to suggest that inflatons have no non-gravitational interaction at all with the particles of the Standard Model.

Monday, September 17, 2007

In the September issue of Scientific American, ardent sceptic Michael Shermer writes an open letter to Messrs. Dawkins, Dennett, Harris and Hitchens, which I reproduce in full here:

Since the turn of the millennium, a new militancy has arisen among religious skeptics in response to three threats to science and freedom: (1) attacks against evolution education and stem cell research; (2) breaks in the barrier separating church and state leading to political preferences for some faiths over others; and (3) fundamentalist terrorism here and abroad. Among many metrics available to track this skeptical movement is the ascension of four books to the august heights of the New York Times best-seller list—Sam Harris's Letter to a Christian Nation (Knopf, 2006), Daniel Dennett's Breaking the Spell (Viking, 2006), Christopher Hitchens's God Is Not Great (Hachette Book Group, 2007) and Richard Dawkins's The God Delusion (Houghton Mifflin, 2006)—that together, in Dawkins's always poignant prose, "raise consciousness to the fact that to be an atheist is a realistic aspiration, and a brave and splendid one. You can be an atheist who is happy, balanced, moral and intellectually fulfilled." Amen, brother.

Whenever religious beliefs conflict with scientific facts or violate principles of political liberty, we must respond with appropriate aplomb. Nevertheless, we should be cautious about irrational exuberance. I suggest that we raise our consciousness one tier higher for the following reasons.

1. Anti-something movements by themselves will fail. Atheists cannot simply define themselves by what they do not believe. As Austrian economist Ludwig von Mises warned his anti-Communist colleagues in the 1950s: "An anti-something movement displays a purely negative attitude. It has no chance whatever to succeed. Its passionate diatribes virtually advertise the program they attack. People must fight for something that they want to achieve, not simply reject an evil, however bad it may be."

2. Positive assertions are necessary. Champion science and reason, as Charles Darwin suggested: "It appears to me (whether rightly or wrongly) that direct arguments against Christianity & theism produce hardly any effect on the public; & freedom of thought is best promoted by the gradual illumination of men's minds which follow[s] from the advance of science. It has, therefore, been always my object to avoid writing on religion, & I have confined myself to science."

3. Rational is as rational does. If it is our goal to raise people's consciousness to the wonders of science and the power of reason, then we must apply science and reason to our own actions. It is irrational to take a hostile or condescending attitude toward religion because by doing so we virtually guarantee that religious people will respond in kind. As Carl Sagan cautioned in "The Burden of Skepticism," a 1987 lecture, "You can get into a habit of thought in which you enjoy making fun of all those other people who don't see things as clearly as you do. We have to guard carefully against it."

4. The golden rule is symmetrical. In the words of the greatest conscious ness raiser of the 20th century, Mart in Luther King, Jr., in his epic "I Have a Dream" speech: "In the process of gaining our rightful place, we must not be guilty of wrong ful deeds. Let us not seek to satisfy our thirst for freedom by drinking from the cup of bitterness and hatred. We must forever conduct our struggle on the high plane of dignity and discipline." If atheists do not want theists to prejudge them in a negative light, then they must not do unto theists the same.

5. Promote freedom of belief and disbelief. A higher moral principle that encompasses both science and religion is the freedom to think, believe and act as we choose, so long as our thoughts, beliefs and actions do not infringe on the equal freedom of others. As long as religion does not threaten science and freedom, we should be respectful and tolerant because our freedom to disbelieve is inextricably bound to the freedom of others to believe.

As King, in addition, noted: "The marvelous new militancy which has engulfed the Negro community must not lead us to a distrust of all white people, for many of our white brothers, as evidenced by their presence here today, have come to realize that their destiny is tied up with our destiny. And they have come to realize that their freedom is inextricably bound to our freedom."

Rational atheism values the truths of science and the power of reason, but the principle of freedom stands above both science and religion.

This is pretty good stuff, but I suspect that Messrs. Dawkins, Dennett, Harris and Hitchens would agree with most, if not all of it. The key proposition is that "As long as religion does not threaten science and freedom, we should be respectful." Messrs Dawkins, Dennett, Harris and Hitchens would simply point out that in most parts of the world, for most of human history, religion has threatened and restricted human freedom. At the present time, religious belief in the United States threatens science and freedom, and in the Islamic regions of the world, there is egregious intolerance towards science and freedom. The problem with religion is that its intolerance towards science and freedom is wholly typical of it.

Sunday, September 16, 2007

In the Autumn of 1994, the Benetton Formula 1 team had been summoned before the World Council of motorsport's governing body, the FIA, to answer charges that it had deliberately removed the filter from a re-fuelling rig to gain a competitive advantage. Fearing exclusion from the World Championship, Benetton hired George Carman QC to represent them in court.

Whilst Carman died from prostate cancer in 2000, he was able to confide to his son, Dominic, the details of a meeting he had with Max Mosley, the President of the FIA, on the night before the hearing. The day after this meeting, Carman chose to offer no defence, but also to request no punishment. No prosecution evidence was presented to the World Council, Mosley performed the summing-up, and no punishment was imposed upon Benetton.

Dominic Carman chose not to include this event in his father's biography, No Ordinary Man, but he was able to recount what happened to journalist, Christian Sylt, who wrote this article.

Wednesday, September 12, 2007

A not inconsiderable portion of September's Physics World, is devoted to string theory. Matthew Chalmers writes a comprehensive survey article on the physics, and Nancy Cartwright/Roman Frigg, from the London School of Economics, write a curiously equivocal article on the philosophy.

Chalmers' article contains the following quote from Leonard Susskind, which caught my attention: "Quantum field theories don’t allow the existence of gravitational forces...String theory not only allows gravity, but gravity is an essential mathematical consequence of the theory."

Now, the claim that quantum field theories don't allow the existence of gravitational forces is slightly misleading. In relativistic quantum theory, each different type of elementary particle corresponds to a Hilbert space equipped with a different unitary, irreducible representation of the Poincare group, (the local symmetry group of space-time). The physically relevant representations of the Poincare group are classified by one continuous parameter, which transpires to be the particle mass, and one discrete parameter, which transpires to be the particle spin. Obtaining these representations is called 'first-quantization'. The graviton, the hypothetical particle of a quantum theory of gravity, corresponds to a particle of mass zero and spin 2. Hence, the graviton corresponds to a well-defined unitary, irreducible representation of the Poincare group in relativistic quantum theory.

From each unitary, irreducible representation of the Poincare group, one can construct another Hilbert space, called a Fock space, and the Fock space is the state space of the quantum field corresponding to the elementary particle in question. This is called 'second-quantization'. Hence, one can construct a well-defined Fock space for the graviton in quantum field theory.

Fock space, however, is the state space for a free field, a field free from interaction with itself or other fields, and there is, as yet, no such thing as a mathematically well-defined quantum field theory of interacting fields. In the case of quantum electrodynamics, one can define interaction Hamiltonians upon Fock space so that, after perturbative calculations have been manipulated by renormalization techniques, reliable scattering amplitudes and cross-sections are obtained. In quantum chromodynamics, even this approach is dubious, and applying such techniques to the quantization of the gravitational field fails completely.

There is, however, another potential approach to the representation of interacting fields. This approach requires Fock space to be abandoned, and for interacting quantum fields to be represented in terms of non-linear mathematical structures. There is a well-defined theory of first-quantized interacting fields, which involves non-linear structures, and just as the second-quantization of a first-quantized free field is a map from a linear vector space into another linear vector space, one would expect the second-quantization of first-quantized interacting fields to be a map from a non-linear space, into another non-linear space. This approach to developing a quantum theory of interacting fields is, I suggest, more likely to bear fruit in the quantization of gravity, than any variation on the string theory programme.

Monday, September 10, 2007

There's a fabulously evocative article by astronaut Jeffrey Hoffman in this week's New Scientist, which describes what it actually feels like to ride on the Space Shuttle. I particularly enjoyed the following:

The most spectacular view of the re-entry light show surrounding the shuttle is towards the rear. Still moving at hypersonic speed, the shuttle is surrounded by shock waves, which form a relatively stable three-dimensional pattern behind the shuttle, much like the wake behind a motor boat. Multicoloured plasma streams flicker irregularly, and where the shock waves converge they form a tiny, brilliant point of light, a steady diamond shining back at us at the temperature of the surface of the sun.

The ceramic tiles that protect us from the heat of re-entry are doing their job, but every once in a while tiny pieces of gap filler material come loose and fly away as bright flashes moving through the wake. Every time I see one go by I think "I hope that wasn't anything important!"

Saturday, September 08, 2007

This used to be the Post Office in Dorchester, Dorset. It was an elegant and historical building. As the photo testifies, however, it is now a Starbucks.

This seems to me to be a deliberate act of cultural vandalism. Starbucks didn't merely open an outlet in Dorchester; no, they wanted to take something which represented values antithetical to their own, something with beauty and architectural heritage, and demonstrate that they could acquire it, sever it from its historical roots, and replace it with their own brand values. A demonstration of cultural hegemony, if you will.

Wednesday, September 05, 2007

One of the strangest trends in modern academia is the writing of books and papers on philosophical issues, by physicists, who do so without having first read any of the relevant philosophical literature. It would be perverse, and wholly lacking in fundamental academic rigour, to write about, say, the properties of the electron, without having first acquainted oneself with the physics literature on the subject, and yet physicists write about the mind, the creation of the universe, the measurement problem in quantum mechanics, non-locality in quantum theory, the many-worlds interpretation of quantum mechanics, etc. etc., without making any effort to read what has already been written in the philosophy of physics. As a consequence, they re-discover ideas and errors which have already been enunciated, often many years previously, in the philosophical literature.

Hence, this two-volume, 1522 page work, 'Philosophy of physics', edited by Jeremy Butterfield and John Earman, will go largely unread by physicists. And notably, even one of the articles within, that written by the general relativist, George Ellis, purports to cover philosophical issues in cosmology, but does so without reference to any of the relevant modern philosophical literature.

Nevertheless, given the £125 pricetag for the book, as a service to those without a hedge-fund, I here reproduce the contents, with hyperlinks to those articles freely downloadable.

Tuesday, September 04, 2007

In my callow naivety some years ago, the first flat I ever rented was heated exclusively by electric storage heaters. Or, I should say, it wasn't heated. The idea of these misbegotten domestic appliances, is that they store heat from the cheap supply of electricity at night, and then release it, when required, during the day. The examples in my flat worked fine, except for the fact that they didn't absorb much heat at night, and the heat they did absorb, gently wafted away during the day, leaving the flat in permafrost in the evening.

Now, whenever I enquire about a flat, the first question I ask is: 'Has it got gas central heating?'

Monday, September 03, 2007

Now, I'm a busy fellow, but a few years back I took the opportunity, with a couple of colleagues, to establish a surveying company.

In the early years, we established a firm foundation for the business, and, building upon this, we genuinely see no boundaries to our future. We now offer two different service packages: the Theodo, which is our premium, fully comprehensive suite of services, targeted at larger organisations; and the Theodo-lite, which is our budget package, ideal for the smaller company. We very much aim to be the benchmark in the surveying industry.

Saturday, September 01, 2007

It is sometimes said that laser light consists of a bunch of photons in the same state. In fact, if a laser is treated as a 'coherent' state of a quantized harmonic oscillator, as is often the case, then this statement is quite false.

The popular science literature often claims that light consists of photons, but according to quantum field theory, photons are merely the excitation quanta of the quantized free electromagnetic field. There are states of the quantized free electromagnetic field in which there are definite numbers of photons present, but there are also states in which there is an indefinite number of photons. Such states can be described as non-particle states of the quantized free electromagnetic field.

Laser light of energy E=hν can be represented by a coherent state |α> of a quantized, frequency ν harmonic oscillator, as follows:

The states denoted as |n> are the energy eigenstates, state |n> consisting of n photons of energy E=hν.

The state |α> is coherent by virtue of the fact that it is an eigenstate of the annihilation operator â:

The eigenvalue is a complex number α = |α|eiθ, and this complex number specifies the phase θ and amplitude |α| of the energy E=hν laser light. The states |n> are eigenstates of the number operator, hence these states are states in which a definite number of photons exist. However, the coherent state is clearly a superposition of these states, and is not itself an eigenstate of the number operator.

Hence, laser light is a non-particle state of the quantized free electromagnetic field.